The future of coal depends on balancing economic growth with environmental responsibility.

我今晨坐在窗前，世界如一个过路人似的，停留了一会儿，向我点点头又走过去了。

The first condition of understanding a foreign country is to smell it.

在量子场论的领域中，真空并非空无一物，而是充满了虚粒子的沸腾大锅。